Dragon Quest IV

I've been playing this game for the DS and I just picked up Torneko into my party and got his boat. Then I went sailing to this place in the south where Hank Hoffman Jr. leaves you to learn how to run his own inn and for some reason Troneko isn't in my party anymore. I was wondering why this is.

I figured it out but for some reason I can only change party members before battle. Anyways I'm on the Marquis Leon or w/e his name is and he keeps killing me with his breath attack. Anyone know some good places to grind at this point?

If I knew the Japanese names, I could help you. Oh wait, Marquis Leon is probably King Leo. In which case, Kiryl (Krift) is an absolute REQUIREMENT, to beat him. I don't know the spell's English name, but he eventually learns that spell that increases all DEF stats for the party. Use this to maximum. Also seal that lion's spells. If you do this, the breath attack becomes the only attack that damages you which makes the boss fight a lot easier. If you really want to grind, the cave to the south of the castle is a good place.

You can also change party members any time so long as the wagon is with you.